1. Field of the Invention
The present invention relates to the field of automobile batteries, and in particular, to a method and an apparatus for automatically computing work accuracy of a battery management system (BMS) offline.
2. Description of Related Art
Vehicles, especially electric vehicles, includes numerous high-voltage electric components, such as a high-voltage battery pack, a high-voltage junction box, an electric motor and controller, an electric air-conditioner and controller, a DC/DC converter, and a charger. A battery powering one or more of these components is one of the most important components. How to effectively and accurately estimate a state of charge (SOC) and a state of power (SOP) of the battery is important for ensuring that the battery does not exceed an allowable battery voltage/current/temperature value while satisfying a power requirement of a vehicle and for ensuring a service life of the battery.
An existing BMS may estimate an SOC and an SOP of an automobile battery pack. Unfortunately, with regard to how to determine whether the estimations are accurate, it is impossible to determine directly by means of measurements. Therefore, it is necessary to compute work accuracy of the BMS to further determine whether estimates of the SOC and SOP are accurate. In an existing method, it is necessary to approximately determine work accuracy of a BMS by performing numerous uncontrolled experiments while the vehicle is running. Such a methodology is both time-consuming and human labor-intensive. Further, computation must be completed while the vehicle is running, and, because in an actual running process of a vehicle, manual operation is needed, resulting in measurement uncertainty, an expected conclusion may not always be obtained.
Chinese Patent CN201010102766.2 provides a test platform for a BMS, where a battery parameter is numerically simulated by using a battery voltage simulator and a constant-current source. Although this method may be automated, in this method, work accuracy of the BMS is computed by numerically simulating the automobile battery rather than being determined based on measurement obtained when operating the battery. During an operation of an automobile battery, numerous parameters are uncontrollable and unpredictable. This numerical simulation platform cannot ensure accurate prediction of the battery behavior, and therefore, may only be appropriate in a controlled laboratory environment and is not applicable to industrial production setting.